Adjustable electrode support for electron discharge tubes



A. K. WING, JR, ADJUSTABLE ELECTRODE SUPPORT FOR July 27, I948. ET AL ELECTRON DISCHARGE TUBES Filed April 4, 1946 1212' A, Mkgdf: BY Aiac'i' INVENTORS.

I ATT Patented July 27, 1948 TED ADJUSTABLE ELECTRODE SUPPORTFOR "ELECTRON DESCI-IARGE. TUBES 'ArthurlKpwing, "J12, Nutley, and Lyle AuBa'cker, Denville, N. 'J.,"assignors to Federal Telephone andRadio Corporation, New York, N. Y., acorporation of Delaware ApplicationApril 4, 1946, SerialNo.659,606

This invention "relates to ele'ctrode mountings,

and particularly to mounting arrangements for electrodes used in vacuum tubes. The principal object isto provide an elfective electrode mounting which'is' adjustable to permit easy alignment of the electrodes.

"An ordinary form of vacuum tube comprises an evacuated envelope containing a number of electrodeswhich are mounted in spaced relationship to each other. The mounted positions of the electrodes relative to each other are usually of considerable importance. The three-electrode form of vacuum tube, "for example, may comprise a cathode, an anode spaced from the cathode, and a gridbetween the cathode and anode. In such an arrangement, it is important thatthe spacing of all parts of'the electrodes relative to each other shall be accurately adjusted and maintained.

Owing to manufacturing variations, it is often desirable or necessary to adjust the positions and alignments of one or more of the electrodes manually by provision ofadjustable mountingmeans; and such mounting means for this purpose have heretofore been proposed. These former expedients have permitted partial adjustment of the electrodes relative to each 1 other, but they have not permitted a full adjustment for both the distance apart andthe'tilt of the electrodes.

According to ourpresent invention, we provide adjustable mounting means whereby a full adjustment of-an electrode may be made both with respect to distance apart andfor the tilt. We carry this outby supporting the electrode to be adjusted by amounting memberor support provided with an arcuate portion whose "radius of curvature is centered at a point relative to which it is desired to position and tilt the electrode. For holding'the mounting-member in position, we provide a clamping'means'within which the arcuate portion is held, this clamping means being providedwith a' corresponding arcuate surface to permit movement of the arcuatemounting member portion relative to the clamping member.

The arrangement is such that movement of the arcuate mounting portion relative to the clamping member provides adjustment for the tilt. The

clamping means itself is made adjustablein a sideways direction was to provide-forthe sidefiClaims. (Cl. 250-27.5)

Fig. 2 is a cross sectional view taken fromithe top at line 2-2iof Fig.1.

In the drawings there areshownthe electrodes of a three-electrode vacuum tube having a centrally located filament type'cathode l centered on a longitudinal axis AA, a cylindrical formof gridZ around the cathode and a cylindrical anode 3 around the grid. Only part of'the tube envelope '4 is shown, as it forms no part of the invention. The centrally located filamentary type cathode l is held in its central position by the two supporting rods 5 and 6 which act as theterminal leads (if the filament and are carried down through the base of the tube in any well known and suitable manner, not shown in" the drawing. The particular mounting means for the anode is not shown, as th only purpose for showing the anode in the drawing is to indicate its position relative to theother electrodes.

The cylindrical shaped control :grid .2 is mounted in accordance with our invention. The grid supportis a conical member 1 fastened to the lower edge of thergrid at the upper edge of the cone at 8, which fits just inside the grid and may be fastened by suitable means suchas'welding. The depending cone 1 is bent at a circular position 8 to form an annular flange "3;: and the flange Hi is shaped in the form of a segment of'a sphere with the radius of curvature at anoint-P at about the central position of the axis of the filament.

Clamping means are provided to hold the flange it of the conical support. The'cla'mping means are in the form of a pair of annular rings Hand l2, which are formed with a pair'of corresponding surfaces l3 and It, also shapedas Segments of spheres having their radii otcurvature centered at the same point Pas the spherical center of flange member Ill. The arrangement is such that part It of the collar iii-extendsthrcughthe 'envelope and is available for making electrical'contact with the grid.

The inner periphery I9 isdrilledand threaded at several places aroundits circumference to receive fastening screws 20 which pass through i holes-2| and 22 of the 'clampingrings "I l-arid t2,

and. through corresponding holes 23 of the flange In.

To provide for adjustment of the grid mounting means, al1theholes 2|, 22 and 23 are made somewhat larger than the diameter of the screws, as shown in Fig. 2. Since the positions of the screws are fixed by the screw holes in flange l5, the oversize dimensions of the holes in the clamping members permit adjustment in the horizontal direction, that is, in any direction perpendicular to the axis A--A of the electrode structure. In this way, the central axis of the cylindrical grid can be made to coincide with the axis A-A of the filament. In spite of the ability to shift the grid in this direction, the axis of the grid may still remain on something of a tilt with respect to the axis and the filament. This tilt can be overcome by shifting the position of the flange Ill relative to the clamping means II and I2. This shift is readily accomplished by moving the segmental flange l a little bit about the aXis P, and the provision for making this adjustment is provided by the oversize dimension of the hole 23 through the flange.

By this arrangement, adjustment for both the tilt of the grid electrode and of its distance from the filament electrode in a sideways direction may readily be accomplished. When the adjustment is finally made, it is held by tightening down the screws 20.

While our invention has been particularly described in connection with a cylindrical grid electrode, it will be understood that it is equally applicable to other electrodes in the tube which it is desired to hold in a particular relative position. Furthermore, the invention is not limited to use with cylindrical electrodes, but may also be used for positioning and supporting electrodes having other shapes. Th invention accordingly, should'not be construed to be limited to the arrangement shown in the drawings, but only as limited by the appended claims.

We claim:

1. Means for supporting an electrode comprising a support for the electrode, a flange attached to the support, said flange being in the shape of a spherical segment centered about a point with reference to which it is desired to position the electrode, and clamping means for holding the flange, said clamping means having surfaces in the form of spherical segments centered about the same point, and means holding the flange between said surfaces.

2. Means for supporting an electrode comprisin a support for the electrode, said support having a portion in the form of a part of a sphere Whose radius of curvature is centered about a pointwith reference to which it is desired to position the electrode, and a clamping means having a surface in the form of a portion of a sphere also centered about the same point, and means holding the spherical portions together.

3. An electrode support comprising an annular flange shaped in the form of a segment of a sphere which is centered about a point with reference to which it is desired to position the electrode, a clamping ring having a surface in the form of aspherical segment having the same radius of curvature as the first-mentioned spherical segment, said spherical segments being capable of being moved relativ to each other and means clamping the two spherical segments together.

4. An electrode support, having an annular flange in the shape of a segment of a sphere, a

pair of clamping rings each having a surface in 4 the form of a spherical segment whose center of curvature is at the same point as the center of curvature of the first-mentioned segment and means clamping the flange between the spherical segmental surfaces of the two clamping rings.

5. An electrode support having a supporting member in the shape of a segment of a sphere, a pair of clamping devices each having a clamping surface in the form of a spherical segment whose center of curvature is at the same point as the center of said sphere, means adjustably posi tioning the member between the spherical segmental surfaces, and means clamping the member between the clamping surfaces and holding the clamping devices in a fixed position.

6. An electrode support having an annular flange in the shape of a segment of a sphere, a pair of clamping rings each having a surface in the form of a spherical segment whose center of curvature is the same point as the center of curvature of the sphere, a fixed supporting member, and fastening means attaching the clamping rings to the fixed member, said clamping rings having oversize holes through which the fastening means pass and said annular flange having oversize holes through which the clamping means also pass, said flange being held between the surfaces of the clamping rings whereby th clamping rings may be moved relative to the fixed supporting member and the flange may be moved relative to the clamping rings.

7. An electrode support comprising a conical supporting member attaching to the electrode, said supporting member having a flange in the form of a segment of a sphere, a pair of clamping rings each having a surface in the form of a spherical segment whose center of curvature is at the same point as the center of curvature of the sphere, said flange being placed between the surfaces of the clamping rings, a fixed supporting member, and fastening devices attached to the fixed supporting member and passing through holes through the rings and the flange, said holes being oversize with respect tothe fastening means whereby the flange may be moved relative to the rings and the rings may be moved relative to the fixed supportin member to provide adjustment of the position and the tilt of the electrode.

8. Means for supporting a cylindrical type of grid in a position around a cathode located within the grid, saidmeans comprising a support for the grid having an annular flange in the shape of a segment of a sphere, a pair of clamping rings each having a surface in the form of a spherical segment whose center of curvature is at the same point as the center of curvature of the sphere, a fixed supporting member and fastening means attaching the clamping rings to the fixed member with the flange sandwiched between the segmental surfaces of the clamping rings, said clamping rings and annular flange having oversize h'oles through which the clamping means pass, whereby the clamping rings may be moved in a direction perpendicular to the longitudinal axis of the grid within the limits of the oversize holes in the rings to adjust the distance of the grid from the cathode, and the flange may be moved relative to the ring surfaces to the limit of the oversize h'ole of the flange to adjust the tilt of the id.

ARTHUR K. WING, JR. LYLE A. BACKER... 

